PyMagedon is a massive multiplayer, survival strategy game. It is free to play.
You play as a part of the ecosystem that constantly evolves and obeys predator-pray relationship dynamics that is found in nature. The game only has the number of predators that the ecosystem can support.
Enemies aren't there just to get you. They have to fight for survival as well.
The game has its own ecosystem. All bots require sufficient nutrition regardless if they are a plant, herbivore ot a predator.